Metal oxide semiconductor (MOS) transistors in integrated circuits (ICs) sometimes have fully silicided (FUSI) gates to reduce the depletion region in the gate, commonly known as poly depletion. Gate silicidation to form FUSI gates is commonly performed prior to source/drain silicidation, to separately optimize the gate silicide and source/drain silicide processes. Forming FUSI gates in this manner can be problematic, due to sensitivity of the gate silicide to various wet process steps in the source/drain silicidation process sequence, which can undesirably etch the gate silicide, causing defective MOS transistors.